Each finger (except the thumb) contains three bony segments and three joints which permit bending (flexion) and straightening (extension) about each joint (FIGS. 1-2). The second joint is called the proximal interphalangeal joint or PIP joint. The PIP joints of the index through small fingers, especially the ring and long fingers, are among the most commonly injured joints in the hand. During recreational activities an individual often holds his or her finger out straight in the fully extended position. If it is then struck on the tip by an object such as a football, a swinging door or a dropping weight, the result is the classic "jammed finger," characterized by a variable amount of swelling around the joint and considerable pain and stiffness when trying to bend the finger.
The anatomy of this injury is fairly simple: the PIP joint is held together by ligaments which traverse the joint and attach to the bony segments on either side of the joint. The collateral ligaments are the structures which prevent side-to-side motion of the joint and only permit normal flexion and extension. Thus when the extended finger is suddenly struck by an object and forced to one side or the other, this is the ligament that will tear (FIG. 3). The "jammed finger", therefore, is a sprain or partial tear of a collateral ligament of the PIP joint. This is the injury that is principally addressed by the present invention.
Partial tears probably make up greater than 95% of all PIP ligament injuries All partial tears or sprains of collateral ligaments are currently treated with the method known as "buddy-taping" (FIG. 4). The injured finger is taped to a normal adjacent digit and active motion is encouraged from the outset. The tape is worn continuously for three weeks, and then during periods of anticipated stress for an additional three weeks. Usually athletes can play during the entire period of treatment. While a PIP sprain is not a serious injury, the pain and swelling will persist for weeks and often months, and normal function of the joint does not return for several months or even up to one year. Many people either do not seek treatment or treat the injury themselves, because they believe the injury is not serious and they resist going to a physician unnecessarily. Others, concerned that something is broken, will go to their doctor or to a nearby Emergency room, only to discover that the X-rays are negative and the injury is not as serious as they had thought. Both groups of people could benefit from an improved and simplified method and dressing for treating this injury.
The current method of buddy-taping, with standard cloth tape available in most Emergency departments and drug stores, often does not hold up to persistent activity during the recommended three to six weeks of total treatment time. The tape often falls apart and many patients will not replace the tape when this occurs because it is inconvenient to retape and there is no suitable alternative. People who don't seek treatment for the sprain might try splinting the finger with some stiff, bulky material at home such as an emery board. This quickly becomes a nuisance and is discarded. It also prevents active movement of the joint, which is desirable during the treatment of the injury.
The preferred treatment during the acute period of the injury, i.e., the first 24-48 hrs., also includes application of cold. Unfortunately, icing a single finger with a large ice pack is often difficult and inconvenient.
Various finger and hand splints are known to the art, but none of these is well adapted for treating PIP joint injuries.
Rigid finger splints are shown in U.S. Pat. No. 4,781,178 to Gordon, U.S. Pat. No. 3,039,460 to Chandler, U.S. Pat. No. 2,022,883 to Gee, U.S. Pat. No. 2,523,606 to Young, U.S. Pat. No. 1,817,212 to Siebrandt and French patent 2,578,740. These splints prevent active movement of the finger, and so are not usable for treating PIP joint injuries.
U.S. Pat. No. 4,953,568 to Theisler discloses an adjustable thumb brace for restraining an injured thumb A resilient band fit around the palm of the hand and is tightened by Velcro-secured straps. Thumb braces of this type are not usable to support the index through fourth fingers to treat a PIP joint injury.
None of the known references discloses or suggests a convenient dressing for treating PIP joint injuries, so as to improve upon the conventional "buddy-taping." Nor do the references suggest a convenient means of applying a cold compress to such an injury.